Photo by MzScarlett / A.K.A. Michelle (Flickr)
This photo shows a large glass of iced black tea, with a slice of lemon added. Lemon is a common addition to iced tea; it causes a chemical change that softens the effect of the tannins, making the tea smoother and slightly less astringent; it also adds a bit of vitamin C and a tangy flavor.
This image is featured in our article on Iced Tea.